DEFINITION: A faulty internal transfer case component that causes a growl or grinding noise in the transfer case.

Review the Symptoms - Transfer Case and perform the necessary inspections.

High/low planetary carrier assembly

1. Inspect the high/low planetary carrier pinion gears for the following conditions:

•	Chipped, bent or deformed teeth

•	Pinion gear needle bearing worn

•	Pinion gear thrust washers missing

•	Seized or binding pinion gears

•	Refer to Transfer Case Cleaning and Inspection in Transfer Case - BW 4482-NR4 Unit Repair.

2. Inspect the high/low planetary carrier input gear for excessive thrust end play.
3. Inspect the input gear teeth for excessive wear or damage.
4. Replace the high/low planetary carrier assembly if any of the above conditions exist. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.

Annulus gear

1. Inspect the annulus gear for teeth damage or wear. Refer to Transfer Case Cleaning and Inspection in Transfer Case - BW 4482-NR4 Unit Repair.
2. Replace the annulus gear if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.

Planetary differential

1. Inspect the planetary differential pinion gears for the following conditions:

•	Chipped, bent or deformed teeth

•	Pinion gear bushings worn

•	Pinion gear thrust washers missing

•	Seized or binding pinion gears

•	Refer to Transfer Case Cleaning and Inspection in Transfer Case - BW 4482-NR4 Unit Repair.

2. Inspect the planetary differential for deformation. Refer to Transfer Case Cleaning and Inspection in Transfer Case - BW 4482-NR4 Unit Repair.
3. Replace the planetary differential assembly if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.

Sun gears

1. Inspect the sun gears for the following conditions:

•	Gear tooth failure

•	Worn or galled thrust surfaces

•	Refer to Transfer Case Cleaning and Inspection in Transfer Case - BW 4482-NR4 Unit Repair.

2. Replace the sun gears if faulty. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.

Thrust washers

1. Inspect the thrust washers for seizure to the planetary differential.
2. Inspect the thrust washers for galling.
3. Replace the thrust washers if faulty and the mating component if damaged. Refer to Transfer Case Disassemble and Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.

Planetary differential not timed properly

1. Inspect the planetary differential for being timed properly. Refer to Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.
2. Properly time the planetary differential gears. Refer to Transfer Case Assemble in Transfer Case - BW 4482-NR4 Unit Repair.